采用显微硬度和力学性能测试及金相显微镜、扫描电镜、透射电镜、X射线衍射等分析手段,研究了Zn含量对Mg-10Gd-4.8Y-0.6Zr合金挤压以及时效处理后合金组织和力学性能的影响.结果表明,在Mg-10Gd-4.8Y-0.6Zr合金中添加Zn元素,有利于细化合金晶粒,提高挤压态的强度.未添加Zn的合金T5态晶粒尺寸约为25 μm,添加1％(质量分数,下同)Zn后,晶粒尺寸约为15μm,Zn含量为3％时,晶粒尺寸约为10μm.当Zn含量为1％时,合金挤压态和时效态的抗拉强度分别为337MPa,397MPa,屈服强度分别为128MPa,148MPa,伸长率分别为10.0％,5.0％,具有较好的综合性能.%Effects of Zn addition on the microstructure and mechanical properties of Mg-10Gd-4. 8Y-0. 6Zr ( mass fraction/% ,the same below) alloy during extrusion and following isothermal aging at 2001 were investigated using digital micro-hardness testing, mechanical testing, optical microscopy(OM) , scanning electron microscopy(SEM) , transimission electron microscopy(TEM) , X-ray diffraction ( XRD ) . The results showed that Zn obviously refined grains of the alloy, and improved mechanical properties of the as-extruded alloys. In T5 condition the average grains of the alloy without Zn addition were about 25 μm; the average grains of the alloys with 1 % Zn addition and 3% Zn addition were about 15 μm and 10 u.m, respectively. For the alloy with 1% Zn addition in the-extruded and aged states, the values of tensile strength reached 337 Mpa and 397 Mpa, yield strength reached 128 Mpa and 148 Mpa, and the ductility rate reached 10.0% and 5.0% respectively, the better comprehensive properties were exhibited.
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